https://www.scientificamerican.com/article/physics-technique-reveals-hidden-bugs-to-bats/

Bats are known for using high-frequency acoustic signals to deftly snatch flying insects from the air at night, even amid dense forests. But more than 40 percent of insectivorous bat species hunt by plucking prey resting on leaves or other surfaces. Because the sound waves bats emit reflect off vegetation at all angles, the returning jumble of echoes should render a leaf-bound insect virtually imperceptible—so scientists have long suspected that bats use clues from vision, smells or prey-generated sounds to help find a motionless meal.